class ActiveRecord::ConnectionAdapters::Table

See {connection.add_foreign_key}[rdoc-ref:SchemaStatements#add_foreign_key]

t.foreign_key(:authors, column: :author_id, primary_key: "id")
t.foreign_key(:authors)

Adds a foreign key to the table using a supplied table name.

def foreign_key(*args, **options)
  raise_on_if_exist_options(options)
  @base.add_foreign_key(name, *args, **options)
end